1. Carbohydrates, Proteins, Lipids, Nucleic Acids
Section 2
Chemistry of Cells
Grade 10 Biology
Fall 2010

2. Bell Ringer
What do cooking oil, sugar, and a piece of meat have in common?

3. Objectives Summarize the characteristics of organic compounds
Compare the structures and function of different types of biomolecules
Describe the components of DNA and RNA
State the main role of ATP in cells

4. Carbon Compounds
Organic compounds contain carbon atoms that are covalently bonded to other elements
Typically hydrogen, oxygen, and other carbon atoms
Four principal classes of organic compounds are found in living things
Carbohydrates, lipids, proteins, nucleic acids

5. Carbohydrates
Carbohydrates: organic compounds made of carbon, hydrogen, and oxygen atoms in the proportion of 1:2:1
Key source of energy
Monosaccharides: building blocks of carbs, single sugars
Ex. Glucose C6H12O6, fructose
Simple sugars such as glucose are a major energy source for cells

6. Carbohydrates
Disaccharides: double sugars formed when two monosaccharides are joined
Ex. Sucrose, consists of glucose and fructose
Polysaccharides: chains of three or more monosaccharides
Ex. Starch
Example of a macromolecule, large molecule made of many smaller molecules
Some function as storehouse of energy, starch and glycogen

7. Lipids
Lipids: non-polar molecules that are not soluble or mostly insoluble in water
Include fats, phospholipids, steroids, and waxes

8. Lipids Phospholipids make up the lipid bilayer of cell membranes
Steroids include cholesterol, found in animal cell membranes

9. Lipids Fats are lipids that store energy
Contains three fatty acids bonded to a glycerol molecule backbone
Glycerol = 3-C organic molecule
Fatty acid = long chain of C atoms, with H atoms bonded to them
Most C atoms in a fatty acid are bonded to either one or two H atoms

10. Lipids
Saturated fatty acid: all of the carbon atoms in the chain are bonded to two hydrogen atoms (except the carbon atoms on the end, which is bonded to three hydrogen atoms)
Most animal fats are saturated
Saturated fatty acids are relatively straight molecules and are generally solid at room temp.

11. Lipids
Unsaturated fatty acid: some of the carbon atoms are linked by a “double” covalent bond, each with only one hydrogen atom, producing kinks in the molecule
Most plant oils, some fish oils are unsaturated
Unsaturated fatty acids generally liquid at room temp.

12. Lipids

13. Proteins
Protein: usually a large molecule formed by linked smaller molecules called amino acids
Amino acids: the building blocks of proteins
Twenty different amino acids are found in proteins
Amino acids can be: polar, non-polar, electrically charged, neutral

14. Proteins
Proteins fold into compact shapes depending on how it’s A.A’s interact with water and one another
Proteins are found in various areas and play important structural functions
Some proteins are enzymes and promote chemical reactions

15. Nucleic Acids
Nucleic acid: long chain of smaller molecules called nucleotides
Nucleotide: has three parts a sugar, a base, and a phosphate group, which contains phosphorous and oxygen atoms
Two types of nucleic acids- DNA and RNA- and each type contains 4 kinds of nucleotides

16. Nucleic Acids
DNA: deoxyribonucleic acid, consists of two strands nucleotides that spiral around each other
Chromosomes contain long strands of DNA, which store hereditary information

17. Nucleic Acids
RNA: ribonucleic acid, may consist of a single strand of nucleotides or of based-paired nucleotides
RNA plays key roles in protein manufacturing

18. ATP
ATP: adenosine triphosphate, is a single nucleotide with two extra energy-storing phosphate groups
When food molecules are broken down inside cells, some of the energy in the molecules is stored temporarily in ATP
Cells need a steady supply of ATP to function

19. Review Name a difference and a similarity between RNA and DNA.
Under the microscope the fat substitute that I spread on my toast has 4 double bonds, and 1 triple bond. Knowing this it must be what type of fatty acid?
The main organic compound that is used as an energy source is?

20. Answers
Difference is RNA is single strand, DNA is double stranded. Similarity they both have nitrogenous bases, sugar backbones, and phosphate groups.
Unsaturated fatty acid.
Carbohydrates.